I'm getting higher voltage then I should at my TPS.

I'm getting 7.29v between (+)Yellow and (-)Green. My understanding is that the yellow wire should always read 5v. When I ground the Yellow wire to the battery's ground I also get the same reading, 7.29v.

When I attempt to calibrate my TPS I can rotate the TPS sensor to achieve .48v at Closed throttle. When I go to Wide Open Throttle it is not possible to achieve the desired 4.5v, thanks to the excessive voltage.

Would the excessive voltage cause a rich condition? Any idea what would cause this?

 

What's the car ??? what's the engine ? please give more detail, is it a stock throttle angle sensor ?

 

Sorry. Was being hasty.

1990 Civic Si running a D16z6, converted to obd1 using a Rywire engine harness and chassis specific subharness, connected to a P28. Stock TPS.

For comparison I also tested the MAP's voltage, which also is off. Stock MAP.

Yellow/Red + body ground = 7.37v. Should be 5v
Yellow/Red + Green/White = 7.38v. Should be 5v
White + Green/White = 5.30v Should be 5v, looks acceptable.

All tests are Key On Engine Off.

 

I am getting this higher voltage on all of my sensors. What regulates the signal flow's voltage to the harness? Or should I not be concerned?

 

for me there is two possibility.

The ECU himself (you should try a known good p28 and see if it changes anything)

or

The voltage regulator (in the alternator) see service manual to test your VR

 

I have two ECU's and get the same voltage regardless of the ECU. Also these tests are done with the Key On Engine Off, taking the alternator out of the loop.

My concern is, the higher voltage hitting the sensors is also leaving the sensors, and returning amplified readings to the ECU. Particularly when it comes to the MAP and TPS.

When it comes to the thermistor-type sensors like the ECT and IAT, I am not as concerned.

Thanks for your take on this. Still a mystery to me.

 

If anybody is feeling charitable and has their head under the hood today, please probe a sensor for a fellow American, but be careful not to bump your head.

Key On Engine Off.

Please share your voltage readings. It's fun. Everyone is doing it. Am I the only one getting 2+ extra volts? I'm tired of feeling alone in my wealthy voltage world.

 

My stock d16a6 is .48v closed, 4.85v open.

You are the only person I know of who has had more voltage than 5.5v at WOT.

Interesting to say the least

 

I think it's in my nature to over think stuff.

After spending hours reading electrical schematics and researching online, I returned to the garage. I started sniffing my Main Relay, then went all over the fuse boxes, reseating and testing. I checked my grounds again, and finally returned to the engine harness. No voltage change. Scratching my head, I decided to get a simple reading of the battery's voltage, it was near 19v!

I didn't know whether to laugh or cry. I assumed my voltage regulator had been malfunctioning, overcharging the battery, and thus, overwhelming my electrical system with juice. I decided to bleed off the charge by turning on the lights and hazards. As I watched with my trusty multimeter, I noticed the lights dim the closer the read out got to 12v. How could this be? I ran inside the house, ripped the smoke detector off the ceiling, tore the 9volt battery out and probed the terminals...

Needless to say, my multimeter was inaccurate. Harbor Freight was having a sale on meters, $6.97. Now my TPS is properly calibrated, and reference is at 5v.

And the moral of the story, when it comes to troubleshooting electrical systems, test your tester before doing anything.

 

I have an 1995 accord and at CT it reads .70 volts and at WOT 4.5.. What could i do?